x−[Pd(dmit)2]2 as a quasi-one-dimensional scalene Heisenberg model

From first principles, we calculate the Heisenberg interactions between neighboring dimers in several compounds within Et$_{n}$Me$_{4-n}X$[Pd(dmit)$_2$]$_2$ (Et = ethyl, Me methyl, dmit 2-thioxo-1,3-dithiole-4,5-dithiolate) family using an atomistic approach; with broken-symmetry density functional theory. In all materials, find a scalene triangular model where strongest exchange coupling along one crystallographic axis is up to three times larger than others and that frustration further enhances this quasi-one-dimensionality. We N\'eel ordering temperature via chain random phase approximation (CRPA). show difference frustrated interchain couplings equivalent single bipartite coupling, favoring long-range magnetic order. temperatures are good agreement experimentally measured values for most compounds.